Industrial process and apparatus



July 25, 1967 E. FAYER v INDUSTRIAL PROCESS AND APPARATUS Filed Aug. 23,1965 Fig. 3

INVENTOR. v ERVI FAYER ATTORNEY United States Patent 3,332,167INDUSTRIAL PROCESS AND APPARATUS Ervin Fayer, Philadelphia, Pa.,assignor t0 Pennsalt Chemicals Corporation, Philadelphia, Pa., acorporation of Pennsylvania Filed Aug. 23, 1965, Ser. No. 481,782 6Claims. (CI. 49-33) This invention relates to a sliding door assemblyfor a pressure chamber and including means by which a flush threshold orsill is provided.

In hyperbaric chambers for medical and other uses space limitations makeit desirable that the door he of sliding rather than of hingedconstruction. In the ordinary sliding door construction for pressurechambers, the door, on the inside of the chamber, moves to a position inalignment with the opening in the door frame and is clamped thereagainstto initiate sealing. Pressure within the chamber will thereafter holdthe door in place while the clamp drops free. In opening, the door isslid to one side.

A problem arises because the door must be larger than and fit over thedoor frame on all sides including the bottom to assure proper seal. Thismeans that a recess must be provided in the floor for the bottom of thedoor. In the past this has required a recess or trough between the doorsill and the floor structure. In many installations the trough in thefloor structure provided for the sliding door can be tolerated. However,it will be understood that when the pressure chamber is used for medicalpurposes and must permit the entry of a wheeled litter bed, a troughcannot be tolerated because it may cause the bed to rattle or worse toget hung up.

There has been need, therefore, for means to cover the trough in thefloor structure provided for the sliding door. Heretofore a simple platehas been provided which is placed over the recess after the door isopened. However, it has been awkard and because it has not beenautomatic it has been bothersome and has become a source of annoyance tohospital personnel.

The present invention provides cover means which automatically move intoplace upon the opening of the door to insure a flush surface at the doorthreshold.

At the same time the means of the invention assure that the recess forthe door will be covered on each and every opening of the door and hencepreclude any possibility that foreign objects will fall into the recessand jam the door.

Other objects of the invention will be apparent from the reading of thefollowing specification including the drawings in which:

FIGURE 1 is a perspective view from the inside of a chamber of a doorarrangement embodying the invention;

FIGURE 2 is a sectional view taken on the line 2-2 of FIGURE 1 andshowing a preferred version of structure embodying the invention and inflat or extended form;

FIGURE 3 is a view taken on the same section line but showing the covermeans in partially retracted form I with the door moved partly towardsits closed position;

FIGURE 4 is a fragmentary sectional view taken on the line 4-4 of FIGURE2; and

FIGURE 5 is a fragmentary sectional view taken on the line 5-5 of FIGURE2.

Briefly, the invention relates to a sliding door for a pressure chamber,the door extending below the pressure chamber threshold in a trough sothat the door may seal against all sides of the door frame, and a covermeans for the trough so that when the door is open the trough will becoveredand present a flat sill.

Referring more specifically to the drawings, the overall arrangementembodying the invention is shown in FIGURE 1 and generally designated10. As shown from the inside of the pressure chamber it includes avertical wall member 12 having a door frame 14 or lip extending inwardof the chamber about the door opening. A sliding door 16 is suspendedfrom a wheeled carriage 18 which rides on a support track 20. Thecarriage may be driven by suitable hydraulic or pneumatic means 22, notpart of this invention.

The door may mount a closing clamp 24 which cooperates with structure 26which may be mounted on the wall 12.

Floor structure 28 comprises a horizontal surface which is at the samelevel as the door frame sill 30. The floor structure 28 is provided witha recess 32 adapted to receive the lower end of the door so that thelower end of the door may overlap the door frame sill 30 to effect aseal thereagainst.

Cover means 34 shown in a preferred embodiment comprise an essential ofthe invention. As shown in FIGURE 2 the cover means 34 may include aseries of links 36 which are pinned together in pairs as at 38 which arebiased toward the folded position (FIG. 3) by axial springs 40 havingtheir ends disposed in pockets 42 provided in the link structures. Asshown in FIGURE 4 the ends of the pinned links abut against each otheron alternate sides of the pin to assure that the links form a planarsurface when the cover means is extended and that they will not deflectdownward from this planar surface in use.

The pairs of links 36 are formed into a continuous assembly by beingconnected to carriages 44 which also may be regarded as links and whichare supported on trunnions 46. The trunnions 46 may be plastic coatedand ride in grooves 48 or tracks in the side walls of the recess 32. Thecarriages provide the support for the links intermediate the ends of thecover means. The opposite ends of the cover means 34 are connectedrespectively to the floor structure at the end of the recess in a hingedconnection 50 and a similar connection 52 on the door. These connectionsare made at the same level and arranged so that the upper surface of thecover 34 (FIG. 2) is flush with the structure 28 and the frame sill 30.

In operation as shown when the door is moved toward its closed positionfrom the open position axial springs 44 bias the links toward thezig-zag accordion arrangement shown in FIGURE 3. When the door iscompletely closed the links form a tight and compact block out of theway of structure around the door. The door may then be clamped shut bymeans 24, 26. In opening the door the means 24, 26 are disengaged andthe door is driven to the position shown in FIGURE 1. Since the covermeans is attached to the door it automatically unfolds to the positionshown in FIGURE 2 and provides a flat surface completely flush with thefloor surface comprising structure 28 and the sill 30 of the door frame.

If desired, the opposite end of the door, that is the rightward end asshown in FIGURE 1, may have attached thereto cover means similar tocover means 34. These second means will assure that the recess left asthe door is slid to closed position will not become a collecting placefor dirt and foreign objects which could jam the door and prevent itsopening. The structure of the second cover means may be similar to thatshown in FIGURES 2 through 5.

It should also be understood that many other arrangements are possiblefor the automatic positioning of the cover means over the door recess32. Such cover means can comprise a simple sliding plate attached to theend of the door which can move on trunnions or simply in the grooves onthe side walls of the recess. However, the illustrated embodiment ispreferred.

Further, it is clear that the invention may be applied to the door of asub-atmospheric chamber, that is, a partial vacuum chamber. In such casethe door would conveniently be on the outside of the chamber.

Therefore, the present invention may be embodied in other specific formswithout departing from the spirit or central attributes thereof and,accordingly, reference should be made to the appended claims rather thanthe foregoing specification as indicating the scope of the invention.

I claim:

1. A door frame having an opening, a floor structure extending up to thedoor frame, a door adapted to move laterally with respect to the openingto a second position to one side of the opening, the floor structurehaving a recess along the path of the door, the recess amply receivingthe lower end of the door, and cover means for said recess adapted tocover the portion of the recess in front of the opening when the door isin the second position and to present a surface flush with the top ofthe floor structure, one end of the cover means being secured to the endof the door closest to the opening when the door is in the secondposition, said cover means comprising a plurality of pivotally connectedlinks, the opposite ends of the plurality of links being respectivelyconnected to the floor structure and the door, and spring means at someof the link points to bias adjacent links toward a given disposition.

2. The combination as described in claim 1 wherein the pivotallyconnected links are hinged together at link points.

3. The combination as described in claim 1 wherein some of the links areprovided with laterally extending trunnions and tracks receiving thetrunnions are provided in the opposite sidewalls of the recess.

4. The combination as described in claim 3 wherein the trunnions areprovided with Teflon covered rollers.

5. A door sill comprising a structure having an elongated openingtherein, the opening adapted to receive the lower end of a sliding door,a cover means for the opening comprising a series of pivoted-togetherlinks, one end of which is attached to the structure at one end thereofand the other end is adapted to be attached to the end of such door,track means provided on the opposite side walls of the opening, somelinks having laterally extending trunnions constrained for slidingmovement in the oppositely disposed tracks, and means biasing someadjacent links toward a folded disposition.

6. A door sill as described in claim 5 wherein the links include atleast one carriage to which the trunnions are attached.

References Cited UNITED STATES PATENTS 2,339,315 1/1944 Alio 49-372 X2,635,685 4/1953 Liebhaber 160-84 X 2,736,931 3/1956 Levine 49-70 DAVIDJ. WILLIAMOWSKY, Primary Examiner.

KENNETH DOWNEY, Examiner.

1. A DOOR FRAME HAVING AN OPENING, A FLOOR STRUCTURE EXTENDING UP TO THEDOOR FRAME, A DOOR ADAPTED TO MOVE LATERALLY WITH RESPECT TO THE OPENINGTO A SECOND POSITION TO ONE SIDE OF THE OPENING, THE FLOOR STRUCTUREHAVING A RECESS ALONG THE PATH OF THE DOOR, THE RECESS AMPLY RECEIVINGTHE LOWER END OF THE DOOR, AND COVER MEANS FOR SAID RECESS ADAPTED TOCOVER THE PORTION OF THE RECESS IN FRONT OF THE OPENING WHEN THE DOOR ISIN THE SECOND POSITION AND TO PRESENT A SURFACE FLUSH WITH THE TOP OFTHE FLOOR STRUCTURE, ONE END OF THE COVER MEANS BEING SECURED TO THE ENDOF THE DOOR CLOSEST TO THE OPENING WHEN THE DOOR IS IN THE SECONDPOSITION, SAID COVER MEANS COMPRISING A PLURALITY OF PIVOTALLY CONNECTEDLINKS, THE OPPOSITE ENDS OF THE PLURALITY OF LINKS BEING RESPECTIVELYCONNECTED TO THE FLOOR STRUCTURE AND THE DOOR, AND SPRING MEANS AT SOMEOF THE LINK POINTS TO BIAS ADJACENT LINKS TOWARD A GIVEN POSITION.